Progressive failure analysis of thin-walled composite columns subjected to uniaxial compression

The paper deals with estimating the load capacity of thin-walled composite columns with C-shaped cross-section subjected to uniform compression. The discussed columns were made of eight-layer GFRP laminate. Three symmetric arrangements of layers were taken into consideration: [0/−45/45/90]S, [90/0/90/0]S, [45/−45/45/−45]S. The experimental research was conducted with the use of the ultimate testing machine and the DIC system Aramis®. Additionally, the numerical analyses were performed employing the Ansys® software. The numerical calculations were conducted with the implementation of the progressive failure algorithm, based on the material property degradation method and implementation of the Hashn's criterion as the damage initiation criterion. In all analyzed cases high consistency of numerical and experimental results was achieved and the failure mechanism included the initiation of the fiber failure in the corner of the columns and its propagation in the direction of the web and the flange of the columns.